How We Rate Evidence

Safety When Used As Directed

When the therapy is used as recommended by medical professionals for a long period of time, what is known about the side effects and risks independent of brain health? Does the therapy raise the risk of depression? Or cancer? What happens when the therapy is taken for many years, which is most likely required for any effective prevention therapy?

The accuracy of the ratings may vary depending on the source of the compound, the health and age of the individual, and the use of other medications that may interact with natural products or drugs. The safest choice is to inform your doctor about all the supplements, natural products, and drugs that you may be taking.

Very likely safe

No serious side effects based on strong scientific evidence or prevalent use with no known concerns.

Probably safe

Side effects are unusual or mild based on strong evidence or the available evidence for long-term use is moderate but does not indicate serious side effects

Some risks

Substantial side effects or health risks are known to occur or the available evidence for long-term use is limited but does not indicate serious side effects

Definite risks

Serious side-effects or risks are known

Unknown

The compound has not been used in humans and thus no safety information is available

Potential to Prevent Dementia

What is the evidence that the potential therapy prevents dementia?

Likely

A protective benefit has been reported with consistent evidence of at least moderate strength

Possibly

Some scientific research suggests benefit but the effect is small, the mechanism is unknown, or the evidence is limited

Controversial

Some scientific evidence suggests benefit while others suggest harm

Unlikely

The strongest forms of available scientific evidence do not suggest a protective effect

Unknown

No quality evidence is available to indicate either a beneficial or harmful effect

Strength of the Evidence

How strong is the evidence for dementia prevention and safety? The initial rating of evidence strength comes from the types of available research. However, the rating is increased or decreased based on consistency and replication of results from different investigators, the potential for bias, the size and duration of the study, and other variables.

Strong

Evidence from at least one appropriately-designed randomized trial or from a meta-analysis of observational studies combined with experimental research in test tubes or animal models

Moderate

Evidence from several observational studies and/or from a randomized trial that is supported by experimental research in test tubes or animal models

Limited

At least some evidence from quality human research, whether observational or experimental, that is supported by experimental research in test tubes or animal models

Very Limited

The available evidence is only from test tubes or animal models

No evidence

There is currently no evidence from animal models or mammalian cells

Disclaimer
The content in Cognitive Vitality is intended solely for informational purposes. IT IS NOT INTENDED TO PROVIDE, AND DOES NOT PROVIDE, ANY MEDICAL ADVICE. IT DOES NOT RECOMMEND OR ENDORSE ANY SPECIFIC ACTIONS OR COURSE OF CONDUCT. Neither the Alzheimer’s Drug Discovery Foundation nor the authors and editors of Cognitive Vitality recommend or endorse any of the drugs, supplements, foods, products, or other choices that may be mentioned or described in this website. We encourage you to consult with your own healthcare providers when making decisions regarding your health.